<template>
  <div class="com-container">
    <div class="title" :style="comStyle">
        <span>{{ '┃ ' + showTitle}}</span>
        <span class="iconfont title-icon" :style="comStyle" @click="showChoice = !showChoice">&#xe6eb;</span>
        <div class="select-con" v-show="showChoice" :style="marginStyle">
            <div class="select-item" v-for="item in selectTypes" :key="item.key" @click="handleSelect(item.key)">
                {{ item.text }}
            </div>
        </div>
    </div>
    <div class="com-chart" ref="trend_ref"></div>
  </div>
</template>

<script>
import { mapState } from 'vuex'
import {getThemeValue} from '@/utils/theme_utils'
export default {
  data() {
    return {
      chartInstance: null,
      allData: null,
      showChoice: false,
      choiceType: 'map',
      //   指明标题的字体大小
      titleFontSize: 0
    };
  },
  methods: {
    // 初始化图表
    initChart() {
      this.chartInstance = this.$echarts.init(this.$refs.trend_ref,'chalk');
      const initOption = {
        xAxis: {
          type: "category",
          boundaryGap: false
        },
        yAxis: {
          type: "value",
        },
        grid:{
            left: '3%',
            top: '35%',
            right: '4%',
            bottom: '1%',
            containLabel: true
        },
        tooltip:{
            trigger:'axis'
        },
        legend:{
           left: 20,
           top: "15%",
           icon:'circle'
        }
      };
      this.chartInstance.setOption(initOption);
    },
    // 获取数据
    getData(res) {
      // const { data: res } = await this.$http.get("trend");
      this.allData = res;
      this.updateChart();
    },
    // 更新图表
    updateChart() {
      // 半透明的颜色值
      const colorArr1 = [
          'rgba(11, 168, 44, 0.5)',
          'rgba(44, 110, 255, 0.5)',
          'rgba(22, 242, 217, 0.5)',
          'rgba(254, 33, 30, 0.5)',
          'rgba(250, 105, 0, 0.5)'
      ]
      // 全透明的颜色值
      const colorArr2 = [
          'rgba(11, 168, 44, 0)',
          'rgba(44, 110, 255, 0)',
          'rgba(22, 242, 217, 0)',
          'rgba(254, 33, 30, 0)',
          'rgba(250, 105, 0, 0)'
      ] 
      // 类目轴的数据
      const timeArr = this.allData.common.month;
      //   y轴的数据
      const valueArr = this.allData[this.choiceType].data;
      const seriesArr = valueArr.map((item, index) => {
        return {
          name: item.name, 
          type: "line",
          data: item.data,
          stack: this.choiceType,
          areaStyle: {
              color: new this.$echarts.graphic.LinearGradient(0, 1, 0, 0, [
                  // %0的颜色值
                  {
                      color:colorArr1[index],
                      offset:0
                  }, 
                  // %100的颜色值
                  {
                      color:colorArr2[index],
                      offset:1
                  } 
              ])
          }
        };
      });
      //   图例的数据
      const lengendArr = valueArr.map((item) => {
        return item.name;
      });
      const dataOption = {
        xAxis: {
          data: timeArr,
        },
        legend:{
            data:lengendArr
        },
        series: seriesArr,
      };
      this.chartInstance.setOption(dataOption);
    },
    // 屏幕适配
    screeAdapter() {
      this.titleFontSize = this.$refs.trend_ref.offsetWidth / 100 * 3.6
      const adaterOption = {
          legend: {
              itemWidth: this.titleFontSize,
              itemHeight: this.titleFontSize,
              itemGap: this.titleFontSize,
              textStyle:{
                  fontSize: this.titleFontSize / 2
              }
          }
      };
      this.chartInstance.setOption(adaterOption);
      this.chartInstance.resize();
    },
    // 切换数据类型
    handleSelect (currentType) {
        this.choiceType = currentType
        this.updateChart()
        this.showChoice = false
    }
  },
  computed: {
    ...mapState(['theme']),
      selectTypes(){
          if (!this.allData) {
              return []
          } else {
              return this.allData.type.filter(item => {
                  return item.key !== this.choiceType
              })
          }
      },
     showTitle () {
         if (!this.allData) {
             return ''
         } else {
             return this.allData[this.choiceType].title
         }
     },
    //  设置给标题的样式
     comStyle () {
         return {
             fontSize: this.titleFontSize + 'px',
             color:getThemeValue(this.theme).titleColor
         }

     },
     marginStyle () {
         return {
             marginLeft: this.titleFontSize + 'px'
         }
     }
  },
  mounted() {
    this.initChart();
    // this.getData();
    // 发送数据给服务器，告诉服务器，我现在需要数据
    this.$socket.send({
      action: 'getData',
      socketType: 'trendData',
      chartName: 'trend',
      value: ''
    })
    window.addEventListener("resize", this.screeAdapter);
    this.screeAdapter();
  },
  destroyed() {
    window.removeEventListener("resize", this.screeAdapter);
    this.$socket.unRegisterCallBack('trendData')
  },
  created () {
    this.$socket.registerCallBack('trendData', this.getData)
  },
  watch: {
    theme () {
      console.log('主题切换了')
      this.chartInstance.dispose()
      this.initChart()
      this.screenAdapter()
      this.updateChart()
    }
  }
};
</script>

<style lang="less" scoped>
.title{
    position: absolute;
    left: 20px;
    top: 20px;
    z-index: 10;
    color: white;
    .title-icon{
        margin-left: 10px;
        cursor: pointer;
    }
    .select-item{
        cursor: pointer;
    }
    .select-con {
        background-color: #222733;
    }
}
</style>